Wednesday, December 2, 2009

Why medicine is not like a parachute

At the recent meeting of the American College of Chest Physicians I went to a session on hospital rapid response teams. This was a talk given by a senior and respected member of the Pulmonary and Critical Care academic community, well published and known. Now, if you are wondering what the heck is a rapid response team, I will tell you: it is a team composed variously of an ICU physician (or a hospitalist, depending on local patterns), a nurse or two, a pharmacist and sometimes other ancillary personnel. The role of this team is to be at the beck and call of the ward nursing staff to evaluate urgently any floor patient whose clinical condition may appear to be deteriorating. The ultimate goal, of course, is to avert a catasprophic emergency called a code, where the patient deteriorates to the point of needing emergent resuscitation.

While such a team makes a lot of sense, no study has convincingly shown that it does what it is meant to do -- either prevent codes or save lives. The presenter, a man quite invested in the sensibility of such teams, was making the point that perhaps we just have not focused on the correct outcomes to measure for this intervention. Ultimately, he said, we should continue to support such teams because of our gestalt that they work. After all, he went on, nobody has tested the effectiveness of the parachute in a randomized controlled trial.

When I heard this, I realized that I had been hearing this comparison a lot lately, of medical interventions to parachutes. And since his statement seemed somehow wrong to me, I started to think about why such an analogy is completely fallacious. And here is the startlingly obvious answer: the number needed to treat (NNT) for a parachute is 1! What this means is that one only needs to "treat" one person with a parachute (or strap it on before jumping out of a plane) to save one life. Now, is there really anything that we do in medicine whose margin of effectiveness comes even close? Last week we argued about a screening test with the NNT of 2,000. And we also talked about a therapy with a NNT of 16 which is not being utilized because of high costs.

So, let's not be intellectually lazy and let's not resort to comparing anything we do in medicine to a parachute. The parachute is made to mitigate the laws of physics, which are inherently more predictable, stable and generalizable than the laws of biology. Instituting a rapid response team may feel good to us, but, in addition to lending no measurable improvements to patient care, it may have the "unintended consequences" of abandoning patients who really need our attention at that moment to better their outcomes.

A similar argument can be made about many interventions whose mere face validity we take as God's own word. We and others have cautioned against such gullibility, particularly in a world that runs with half-truths and misinformation under the banner of quality measures. None of us has the cause to be so self-congratulatory as to compare our wares to the parachute. Now more than ever, experts need to think and present critically, soberly and objectively, lest we continue the trend of parochialism in our out-of-control disease care system.    


  1. I take issue with the claim that the purpose of a RRT team " to be at the beck and call of the ward nursing staff..." It hardly seems worth mentioning that while physicians are considered "assets" for the hospital, nurses fall sqarely into the "costs" column. I can't think of a single hospital operation/policy or benefit that exists solely for the sake of nursing.

    As a critical care nurse who is often called upon to respond to RRT calls, I can tell you it's no fun for us, either. It has the "unintended consequence" of taking a nurse out of staffing (which is often short to begin with) and ties him/her up for as much as three hours at a time (not only do we have to assess, start IVs, draw labs, give meds, etc, but we also are required to accompany the patient on any transports -such as CT or MRI- and sometimes get stuck waiting while a bed is made available in a step-down or ICU).

    The important question is whether the RRT has any value for the patient, and if it takes calling a rapid response to get needed treatment, then I guess it does.

  2. Dear Anonymous,

    Apologies for sounding like I disparaged the nursing profession -- this was not my intention. I fully agree it is all members of the RRT, including nurses, that may be dragged away from other important business.

    I also could not agree more with your last statement that "The important question is whether the RRT has any value for the patient, and if it takes calling a rapid response to get needed treatment, then I guess it does." In fact, I am asserting that no study has been able to show convincingly that an RRT changes patient outcomes, no matter how much face validity the concept has.

    Thank you for your thoughtful comment!

  3. Funny, right after I read this I read "Rapid Response Teams and Continuous Quality Improvement" in the current edition of Patient Safety & Quality Healthcare.
    As Wachter noted in his current article from Health Affair (Jan '10), measuring patient safety is still a great challenge. The writers of the PSQH article were apparently also unable to quantify a real reduction in harm on a per-patient basis (at least such measures were not included in the article). However, their RRTs follow a process to identify trends and evaluate methods for process improvement which their data show has led to overal improvement of care at their facility. Measuring results, not on an individual "parachute for one" level, but on a systems level, could support the use of RRTs. Granted, the Advocate Good Sam experience was not a "study," but their experience should be taken into consideration before throwing the RRT out with the bathwater. Thanks for starting the discussion!
    Becca Price

  4. Rebecca,

    Thanks for your comment. What is described in the PSQH article is all well and good, and kudos to them for identifying (and rectifying? I put a question mark because I am not sure if the results are real or due to chance) a modifiable situation. I am just not sure that the RRT is the most efficient way to do this. I am also not sure how many balls were dropped in other parts of the hospital because so many bodies (and minds) were tied up in something that has not shown any hard improvements.

    I am not saying that other outcomes, such as identifying how many events are related to narcotics or mentoring of the floor staff, are not important. I am merely pointing out that the RRT studies have not disproved the original null hypothesis, and this is problematic. Other aims, such as narcotic overprescribing or staff education, while important, may not be best filled by an RRT.

    Thanks again.

  5. Good point, and I am happy to see the renewed focus on RRT effectiveness. Others have made your same point re: not disproving the null hypothesis, and still we have not seen any studies. It's like the weather-everyone's talking about it (off and on anyway), but nobody's doing anything about it.
    It seems to me that in Advocate's situation they have found some benefit to their use of RRTs, but have not correlated that with a reduction of harm. If that were the case, an ROI estimate might be computed that could support the funding of at least a partially dedicated RRT staff to lessen the negative impact on staff:patient ratio...?
    I do know from my own experience, I really could have used one during many of my mother's acute admissions. Which gets to the next question: WHY are these teams activated in the first place? Is the bedside caregiver calling, the patient, or both?

  6. Rebecca,

    I think you hit the nail on the head -- staffing.

    As for who activates these teams, there are different models. Inmost hospitals it is the nursing staff that makes the call. Some have experimented with families calling the RRT, and the results have been variable.

    Thanks again for your comments.